There is considerable prior art relating to the synthesis of trimethylsilylated silicas from sodium silicate and trimethylchlorosilane and/or hexamethyldisiloxane using aromatic solvents, such as xylene. The prior art trimethylsilylated silicas produced according to these methods typically are of broad polydispersity. It is also known in the prior art that the trimethylsilylated silicas may be combined with polydimethylsiloxanes or cyclodimethylsiloxanes with removal of the aromatic solvent to produce mixtures known to the cosmetic industry by INCI nomenclature as trimethylsiloxysilicate in dimethicone or trimethylsiloxysilicate in cyclomethicone. New information has recently been published about toxicity characteristics of octamethylcyclotetrasiloxane, which is a common component of many cosmetic formulations.
Additional problems relating to the prior art compositions are that complete removal of the aromatic solvents used in the preparation of the trimethylsilylated silicas of the prior art is difficult to accomplish. The odor of trace amounts of aromatic solvents, even at the level of a few parts per million, is generally readily detectable.
Thus it would be desirable if non-toxic alternatives to the use of this material would be desirable, and preferred. Additionally, improvements in odor and other cosmetic characteristics would likewise be beneficial.